1. Field of the Invention
The invention relates generally to the field of programmable heating, ventilation, and air conditioning (HVAC) systems. More particularly, the invention relates to energy saving programmable HVAC systems. Specifically, a preferred implementation of the invention relates to a usage monitoring programmable HVAC system.
2. Discussion of the Related Art
Heating, ventilation, and air conditioning (HVAC) systems consume a large amount of energy. Commonly, heating and cooling operations are controlled automatically with a thermostat or plurality of thermostats which initiate these operations according to preset temperature limits. The thermostat can be located at a predetermined central local or the plurality of thermostats can be located at a predetermined plurality of locations. The thermostats are capable of detecting changes in room temperature. When the room temperature fluctuates outside the preset high and low temperature limits, the thermostats can trigger a heating, ventilation, and air conditioning unit to heat or cool the room, thus maintaining the room temperature between the preset limits. The thermostats regulate room temperature in this manner regardless of whether or not the building is occupied. Since many buildings may be unoccupied for certain periods of time, the continuous operation of such conventional HVAC systems would result in wastage of a large amount of energy. Attempts have been made to reduce energy wastage by including a timer that simply terminates HVAC system function during a preset interval. Such provision is often impractical since most buildings do not have regular occupancy patterns.
Another problem associated with conventional HVAC systems is the unavailability of personalized billing. Generally, all users of a conventional HVAC system have to pay an equal portion of fixed and variable costs associated with continued operations of the HVAC system. As a result, users often have to pay for HVAC services used by another user.
Heretofore, the requirements of energy conservation and personalized billing referred to above have not been fully met. What is needed is a solution that simultaneously addresses both of these requirements.
There is a need for the following embodiments. Of course, the invention is not limited to these embodiments.
According to an aspect of the invention, a method comprises: a method, comprises: providing a usage monitoring heating ventilation and air conditioning control system, the usage monitoring heating ventilation and air conditioning control system including a programmable digital thermostat with an on board memory; issuing personal identification numbers to each of a plurality of system users; associating each of the plurality of system users with at least one of a plurality of user types; storing the personal identification numbers in a first data structure in the on board memory; and linking each one of a plurality of entries in the first data structure by reference to at least one of a plurality of entries in a second data structure in the on board memory, the second data structure including a list of user types. According to another aspect of the invention, a method, comprises: receiving a request for an additional period of heating ventilation and air conditioning system services from a requesting system user, the requesting system user composing a plurality of system users; maintaining a data structure in an on board memory of a programmable thermostat, the data structure including a list of time entries, each time entry associated with one of the plurality of system users; and updating the data structure by adding a duration in units of time to the time associated with the requesting system user. According to another aspect of the invention, an apparatus, comprises: a microcontroller; a digital temperature sensor coupled to the microcontroller; a liquid crystal display coupled to the microcontroller; a set of cursor buttons coupled to the microcontroller; an electrically erasable programmable read-only memory coupled to the microcontroller; an upload capable connector coupled to the electronically erasable programmable read-only memory; a real time clock coupled to the microcontroller; and a back up power supply coupled to the real time clock. According to another aspect of the invention, a method, comprises regulating user access to an interactive user interface of a programmable thermostat, each user identified by a personal identification number associated with a user type selected from the group consisting of building owners, maintenance personnel, building tenants, and manufacturers.
These, and other, embodiments of the invention will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following description, while indicating various embodiments of the invention and numerous specific details thereof, is given by way of illustration and not of limitation. Many substitutions, modifications, additions and/or rearrangements may be made within the scope of the invention without departing from the spirit thereof, and the invention includes all such substitutions, modifications, additions and/or rearrangements.